Pneumatically bundled yarn



y 1970 MOTOHIRO TSURUTA ETAL 3,509,709

PNEUMATICALLY BUNDLED YARN Filed June 4. 1968 2 Sheets-Sheet 1 y 9 MOTOHIRO TSURUTA ETAL 3,509,709

PNEUMATICALLY BUNDLED YARN I Filed June 4. 1968 2 Sheets-Sheet 2 United States Patent US. Cl. 57-140 3 Claims ABSTRACT OF THE DISCLOSURE The present invention relates to pneumatically bundled yarn having good running and handling properties, having substantially no twist as a whole, and being composed of at least 3 monofilaments forming a plurality of repetitive units. Each unit includes 2 sections entwisted in the opposite directions and a no-twist section located between them, each twisted section including a plurality of subsections formed by entwisting one or more monofilaments with random others, and further relates to a process and apparatus for producing the same wherein at least 3 monofilaments are passed a steady fluid stream flowing in the vortex.

BACKGROUND OF THE INVENTION The present invention relates to yarn. More particularly, the present invention relates to pneumatically bundled yarn. The pneumatically bundled yarn obtained by the process of the present invention has good cohesion properties and beautiful appearance, and moreover can be treated advantageously with ease equal or superior to that of the conventional true twist yarn in various textile operations. conventionally, textile yarn is truely twisted and sometimes further sized as well so as to improve the running and handling properties. If yarn having suflicient handling and running properties could be obtained with out necessitating a true twist operation, readily apparent advantages would thereby be realized. It is therefore desired to obtain a coherent yarn bundle without true twisting so as to give good running and handling properties.

Several attempts have been suggested for this purpose. In one such process, filaments composing a multifilamentary yarn are bundled with each other in extremel irregular state by passing through a vortex or turbulent stream of the fluid jet. The yarn thus obtained has however disadvantages, such as poor uniformity, inferior appearance, and liability to separation of filaments when compared with conventional true twist yarn because of the use of the irregular vortex or turbulent fluid stream. Additionally, the yarn obtained is liable to take at least a partly ribbon-like form. These defects can give rise to deteriorated commercial value.

SUMMARY OF THE INVENTION Accordingly among the principal objects of the present invention is to provide a pneumatically bundled yarn without such defects and with good handling and running properties at least equal to those obtained by conventional true twist yarns.

Other objects and features according to the present invention will be apparent upon reading the following specification and claims.

3,509,709 Patented May 5, 1970 According to the present invention, there is provided a pneumatically bundled yarn, having the following characteristics:

(a) The yarn is composed of at least 3 monofilaments,

(b) The yarn is formed by a plurality of repetitive units, each of which includes a S-twisted section, a Z-twiste-d section and a no-twist section located between them, but has as a whole substantially no twist,

(c) The twisted sections include respectively at least one subsection composed of at least two monofilaments twisted in the same direction as that of the twisted section,

(d) One or more monofilaments are at least partly entwisted with one or more other random monofilaments so as to form the said subsection.

In the specification and claims, the term having substantially 11o twist means that having twists of no more than about 50 turns per meter. Numbers of twists as such are considered in various textile operations as substantially no twist. The term repetitive units does not mean that each and all units have a substantially similar construction regarding, for example, numbers of twists, dimensional values, etc., but means only that each unit includes similarly three sections, i.e., two sections twisted in opposite directions respectively and one section having no twist.

DRAWING FIG. 1 schematically illustrates a side view of a preferred embodiment of the yarn of the present invention;

FIG. 2 shows a perspective view of an embodiment of the apparatus according to the present invention;

FIG. 3 shows a cross sectional view of the body portion of the apparatus shown in FIG. 2;

FIGS. 4 to 7 show respectively cross sectional views of the apparatus shown in FIG. 2 on the lines A-A, BB, CC and D-D; and

FIG. 8 shows schematically the arrangements of the devices used in the following examples.

Since the construction of the pneumatically bundled yarn according to the present invention is very complicated and may vary with various factors such as, for example, numbers of twists of raw filaments, numbers of twists of the yarn obtained, shape and dimensional values of raw filaments and the yarn obtained, etc., it is advantageous to describe the construction of the yarn with reference to FIG. 1 of the accompanying drawings showing schematically a preferred embodiment of the instant yarn.

In FIG. 1, the yarn is composed of 4 monofilaments F F F and F and is formed by a plurality of repetitive units. Each unit includes two sections A and C twisted in opposite directions respectively, i.e., in the S- and Z- directions, or vice versa, and a no-twist section B located between the sections A and C. But the yarn as a whole has substantially no twist or twists of not more than about 50 turns per meter. The section A includes at least one subsection a -a (except a and 0 consisting of only one monofilament) composed of at least two monofilaments twisted in the same direction as the section A. The construction of the section C and subsections C1-C8 (except consisting of only one monofilament is analogous to that of the section A and subsections il -(Z A no-twist section B located between the sections A and C is substantially composed of a plurality of monofilaments having no twist. At least one monofilament, e.g., F and F transfers respectively from the subsections a and a to the adjacent subsection a.,. In other words, each and all subsections are defined by transferring one or more monofilaments from one subsection to another. In this manner, the yarn is composed of a 3 plurality of aforementioned units so that the sections are provided in order of A, B, C, B, A and so on. Regarding a selected monofilarnent, it is possible to form a subsection with one or more other monofilaments or alternatively remain by itself among subsections. Due to the cohesive property inherent to textile monofilament and enforced twists, the instant yarn is compact and cherent so that it is possible to use the yarn in place of conventional true twist yarn for various textile operations.

According to the present invention, there is also provided a process for producing pneumatically bundled yarn, characterized by that at least 3 monofilarnents are passed under a tension through a steady fluid stream flowing in a spiral, said monofilaments having substantially no twist.

When these monofilaments are passed through a steady stream of a fluid flowing in a spiral under tension, they are first subjected to a temporary twisting in the stream and are then, according to our observation, complicatedly twisted, entwisted, untwisted, overtwisted and/or zerotwisted at the outlet of the spiral stream. The result obtained by these combined eifects on the monofilaments at the outlet is that the yarn bundle according to the present invention can be formed. The phenomena occurring at the outlet depends upon various factors, such as, for example, tension and numbers of the monofilaments, velocity and pressure of the steady stream, shape and dimensional values of the spiral used, etc., which are so complicated that it may be difficult to analyze them completely. We assume however that the end effect at the outlet of the steady stream flowing in the spiral is one of the decisive factors thereon. Various numerical values in the undergoing specification have therefore been determined mainly by means of extensive experiments.

Any fluid which is harmless to textile filaments and yarns may be used for the purpose of the present invention, preferably, under a gauge pressure of about 1-7 kg./crr1. measured at the inlet 15 (FIG. 2). Taking into account the availability and cost requirements, it is advantageous to use air at or above ambient temperature, or steam above 100 C.

According to a further feature of the present invention, better results such as a low d value (the term d value will be defined infra) can be obtained by wetting the monofilaments with a suitable substance, such as, for example, water or a surface active agent, in advance of their passing through the steady spiral-flowing fluid stream.

One embodiment of the process according to the present invention specifically directed to the production of pneumatically bundled yarn in a relaxed state is characterized by the fact that the monofilarnents are over-fed into the spiral fluid stream. Similar results can also be achieved by over-feeding and heat-setting the yarn bundle obtained by the instant process.

The process of the present invention can be advantageously incorporated with various other textile operations. For example, it is possible to treat the monofilaments put out from the spinning nozzle in the manner according to the present invention. It is also possible to treat the already drawn filaments or those during drawing in the manner according to the present invention.

The process of the present invention can be carried out with a rapid speed such as, e.g., more than 300 meters/ minute. Various filaments including, e.g., drawn filaments and undrawn filaments can be treated according to this process, but especially good results can be obtained by the use of various man-made fibers such as, regenerated fibers, or synthetic fibers (for example, polyamide fibers, polyester fibers, polyacrylonitrile fibers, polyolefines fibers, polyvinyl alcohol fibers, fibers made of copolymer thereof, etc.).

The process for producing pneumatically bundled yarn according to the present invention can be advantageously carried out by using an apparatus which is characterized by (a) a fluid source for generating a fluid stream, (b) a fluid supply means being located between said fluid source and a converter and feeding said fluid stream into the converter, (c) a converter for converting said fluid stream into a steady stream flowing in a spiral towards its outlet, and (d) a yarn guide being located at least partly inside of said fluid supply means so as to project into the inside of said converter substantially in axial alignment, and guiding a plurality of monofilaments to be bundled straight through said steady stream flowing in the spiral in its axial direction in such a manner that any unsteady fluid stream would not give a deteriorative influence upon said monofilaments.

As for the fluid source, any conventional fluid generating means can be used. With respect to the converter, it is possible to use any twist pipe, as far as the following conditions are satisfied:

(l) The axis of the twist pipe is a straight line and is located at the inside thereof.

(2) Llgb/alllfl in which a and b represent respectively the minimum and maximum distances between the center line of the twist pipe and its inner Wall.

(3) It is preferred to use a twist pipe at least one symmetrical axis in its cross section, for example, those taking the ellipse form, rectangular form, rounded rectangular form, oval form, etc.

The shape and dimensional values of the twist pipe according to the present invention can be determined preferably by experiments. It has been found that good results can be obtained, for example, by using a twist pipe having an elliptical cross section, a length of 2-30 cm. and a pitch of l-20 turns/ 10 cm. under the following conditions:

Fluid pressure measured at an inlet: 1-7 kg./cm. Types of fluid: air, nitrogen gas, or steam. Tension of filaments: 0.0l0.5 grarn/ denier. Fluid temperature: at or above ambient temperature.

Referring to FIGS. 2 and 3, the apparatus has a fluid source (not shown), a fluid supply means 11, a converter 12 and a depicted yarn guide 13. The fluid source is connected to an inlet 15 of the fluid supply means 11 so as to supply a fluid stream into the converter 12 affixed to the fluid supply means 11 at its center portion, although it is also possible to supply the fluid therein at any desired portion of the fluid supply means when no deteriorative influence is observed. One end of the fluid supply means is connected to the converter 12 in axial alignment relationship. 'Ihe yarn guide 13 is located in the inside of the fluid supply means 11 in axial alignment with the converter 12 so as to feed the filaments into the converter 12.

For the purpose of preventing any deteriorative influence of the fluid stream in advance of conversion into the steady stream, the yarn guide is composed of a small pipe having two openings 16 and 17 at each end. The converter 12 converts the fluid stream received from the fluid supply means 11 into a steady stream flowing in a spiral, through which the filaments guided by the yarn guide 13 are passed so as to be subjected to the pneumatic bundling according to the present invention. The converter 12 has a substantially elliptical body and is connected to the fluid supply means 11 by means of a connector 14, although various forms other than the ellipse form can be used for this purpose.

PREFERRED EMBODIMENTS OF THE INVENTION The following nonlimitative examples illustrate the invention, in which the degree of the separation of the obtained yarn is designated as at value (low d values mean high cohesion properties) determined in the following manner:

A yarn sample about 2 meters in length was hung by fixing its upper end and at the same time by loading its lower end with a load of 0.3 gram/denier. A hook having a weight of (deniers of monofilament (3/5)) grams was then inserted at its upper end. After the hook moved downwardly and stopped, the distance of the movement of the hook was measured. Similar measurements were repeated 50 times. From the obtained values, there was yielded an arithmetic mean value representing d value.

As shown in Table 1, several embodiments of the apparatus according to the present invention having different cross sectional forms and dimensional values were used in examples.

TAB LE 1 (A) Oval Is 5I0 (G)-.- Rounded rectangle 1. 0X3.0

Example No.:

1 Nylgn 6 (70/24) m mmromm was, ooo ccooocoococcooooooooocoo Key to Table 1:

(1) Type of apparatus used. (2) Cross sectional form of the twist pipe. (3) a (mrn.) b (mm.). (4) b/ a.

(in (3) and (4), a and b represent respectively the minimum and maximum distance between the center line of the twist pipe and its inner wall).

(5) Length of the twist pipe, mm. (6) Pitch of the twist pipe, tums/ 10 cm. (7) Diameter of fluid supply means, mm.

Table 2 represents, for comparison purposes, the results obtained from the experiments carried out in a similar manner to that described above by using commercial nylon 6 yarns available in Japan.

TABLE 2 Sample No.:

1 Nylon 6... 100 70/24 200 2 -do 150 70/24 200 3 do 100 70/24 200 32.3

Remarks:

(A) Type of fiber (B) Type of apparatus (C) Total deniers/filaments (D) Twist, turns/ meter (E) Separation, d

In this table, as Samples 1 and 2, the nylon 6 yarns Types 100 and 150 available from Nippon Rayon K.K., Japan, were respectively used, and as Sample 3, the

Air Ambient temperature 1.5 do do 6 sample yarn was prepared by twisting the said yarn Type additionally so as to give a total twist of 200 turns/ meter, which is likely to fall into the range used conventionally by numerous fabric manufacturers for various practical purposes.

EXAMPLES 1 THROUGH 33 In Examples 1 through 33 shown in Table 3A, pneumatically bundled yarns were produced by using different embodiments of the apparatus according to the present invention as shown in Table 1 under different operational conditions. With reference to FIG. 8 of the accompanying drawings, filaments (composed of monofilaments) were fed from a package 2 through a tensor 3 and Godet roller 41 to the apparatus. The pneumatically bundled yarn obtained was fed through Godet rollers 42 to a package 5.

TABLE 3A Key to Table 3A:

(A) Type of filaments (total deniers/ filaments).

*1 Polyethylene terephthalate.

*2 Polyacrylonitrile.

*3 Polyethylene oxybenzoate.

*4 Polypropylene oxybenzoate.

Raw filaments twist (turns/meter).

Type of apparatus used (same as Table 1). (D) Kind of fluid.

(E) Fluid temperature.

(F) Fluid pressure (kg./cm.

(G) Tension (grams/total deniers).

(H) Passing speed (meter/minute).

(I) Separation (d).

EXAMPLES 34 TO 38 In Examples 34 to 38 shown in Table 3B, raw filaments were first treated with an apparatus according to the present invention and were over-fed and heat-set to yield a relaxed pneumatically bundled yarn, respectively.

EXAMPLES 39 TO 42 In Examples 39 to 42 shown in Table 3B, raw filaments were first over-fed and heat-set in a conventional manner, and were then treated with an apparatus according to the present invention to yield pneumatically bundled yarn in relaxed state, respectively.

EXAMPLES 43 TO 46 In Examples 43 to 46 shown in Table 3B, raw filaments were treated with :a heated fluid, through which they were over-fed between Goddet rollers 41 and 42 so as to pass, to yield relaxed pneumatically bundled yarn, respectively.

bundle obtained had a good boil shrinkage value of 8.0% and a at value of 3.2 cm.

TABLE 33 Example No.

34 Nylon 6 (70/24) A 4 /70 7 5. 7 8. 2 35 do 0 A 4 4/70 0 5.1 9.4 0 A 4 5/70 7 4.6 8.0 0 A 4 4/70 8 5.9 6.9 G 5 6/70 7 8.5 8.2 0 A 4 5/70 7 5. 5 7.8 0 A 4 4/70 6 5.3 8.8 41 *5 FEE (70/34) 0 A 4 4/70 8 5. 5 0. O 42 Nylon 66 (70/34). 0 A 4 6/70 7 5.1 8.7 0 F 3 6/70 8 3.9 5.9 0 F 4 70 7 5.0 8.3 0 F 4 5/70 .5 4.1 7.9 46 *3 FEB (70/24) 20 F 4 5/70 7 4.8 8.6

Key to Table 3B:

(A)-(I) same as Table 3A *1, *3 same as Table 3A (J Temperature of heater C.)

(K) Length of heater (mm.)

(L) Over-feeding ratio (percent) (M) Shrinkage in boiling water (percent) "5 Copolyester-ether; Copolymer consisting of two different recurring units composed of 50 mol percent ethylene units and 50 mol percent ethylene 1.4 diphenoxy butane p,p'dicarboxylate units In the following Examples 474.), after Wetting with water or with a wetting agent, raw filaments were treated with the apparatus according to the present invention, respectively. From these examples, it is apparent that better results such as lower d values can in general be obtained by wetting raw filaments with a suitable wetting agent or with water in advance to the treatment with the apparatus according to the present invention.

EXAMPLE 47 After wetting with water, nylon 6 filaments (70 deniers/24 filaments; no twist) were passed through an apparatus according to the present invention (type A) under a tension of 6.5 g./70 den. and with a speed of S00 meters/minute. Air was used as a fluid under a pressure of 4 kg./cm. The obtained 4 value was 2.8 cm. For comparison purpose, a similar treatment was carried out without wetting with water to give a at value of 6.1 cm.

EXAMPLE 48 After wetting with an aqueous solution (1%) of Carbowax (trade name of a surface active agent available from Ipposha Yushi Kogyo K.K., Japan), nylon 6 filaments (70 deniers/24 filaments; no twist) were passed through the apparatus according to the present invention (type A) in which air was used as a fluid under a pressure of 4 kg./cm. under a tension of 6.5 g./70 den.

The pneumatically bundled yarn obtained was overfed at a rate of 7% and was carried through a heater having a length of 40 mm. at 180 C. to a package with a winding speed of 400 meters/minute. The relaxed yarn EXAMPLE 49 Nylon 6 filaments (70 deniers/24 filaments; no twist) were over-fed at a range of 7% and were passed through a heater having a length of 400 mm. at 185 C. After this treatment the filaments were wetted with Water, were passed through an apparatus according to the present invention (type F) and were wound on a package with a winding speed of 450 meters/minute. Air Was used as a fluid :at ambient temperature and under a pressure of 4 kg./cm. A tension of 5 g./ 70 deniers were loaded on the filaments. The obtained pneumatically bundled yarn had a boil shrinkage of 7.5% and a d value of 3.8 cm.

EXAMPLE 50' Nylon 6 filaments (220 deniers/24 filaments; no twist) were melt spun and were passed through the apparatus according to the present invention (Type F) with a spinning speed of 600 meters/minute. Air was used as a fluid under a pressure of 4 kg./cm. and the filaments were loaded with a tension of 2.5 g./220 deniers. This treatment was carried out at ambient temperature to yield a at value of 1.5 cm. The undrawn yarn was then drawn at a draw ratio 3.2 with a speed of 500 meters/minute. The drawn yarn (69 deniers/24 filaments) had a d value of 15.3 cm.

EXAMPLE 51 Nylon 6 filaments (220 deniers/24 filaments; undrawn; no twist) were drawn at a draw ratio of 3.2 by the use of a drawn winder of conventional type and were fed to a package through the apparatus according to the present invention (Type A) with a speed of 600 meters/ minute. Air was used as a fluid at ambient temperature under a pressure of 5 kg./cm. There was obtained a pneumatically bundled yarn (69 deniers/24 filaments) having a d value of 4.1 cm.

What is claimed is:

1. A pneumatically bundled yarn characterized by the following:

(a) the yarn is composed of at least 3 monofilaments,

(b) the yarn is formed by a plurality of repetitive units, each of which includes a S-twisted section, a Z-twisted section and a no-twist section located between the S and Z-twisted sections, but the yarn as a whole has substantially no twist,

(c) each of said twisted sections includes respectively at least one subsection composed of at least two monofilaments twisted in the same direction as that of said twisted direction, and

(d) one or more monofilaments are at least partly entwisted with one or more other random monofilaments so as to form the said subsection.

2. A pneumatically bundled yarn of claim 1 in which the yarn has twists of not more than about turns per meter.

References Cited UNITED STATES PATENTS 7/1961 Bunting et a1. 57-34 3/1963 Field 57-140 XR 10 3,225,533 12/1965 Henshaw 57-34 3,306,023 2/1967 Henshaw et a1. 57-140 XR 3,434,275 3/ 1969 Backer et a1. 57-139 STANLEY N. GILREATH, Primary Examiner W. H. SCHROEDER, Assistant Examiner U.S. Cl. X.R. 5734, 157 

